miniVNA Android controller v0.9.4-6

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ik2ycw
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miniVNA Android controller v0.9.4-6

Post by ik2ycw »

Hello Dan,
I am using since few days your application and it's working great.
I do have a problem with the frequency reading.

If I am using the miniVNA PRO with his regualar software, I get the frequency correct, if I am using the Android software, the frequency readings are around 300Khz higher, for example on 7 Mhz band,
my antenna has a dip around 7,088 KHZ, i get that with the mini VNA PRO and his standard software, also I get confirmation with my Icom 7800 and from the SDR kits.
With the miniVNA PRO and the Android software I get a dip around 7,342 Khz, similar situation on other bands ( the difference is not the same , it does increase with higher bands).
Of course I do an accurate calibration when I connect to the Android software.

My MiniVNA pro is quite old, serial number 00025.

If you can help me, I will appreciate.

Thanks and keep up the great work.

Claudio
IK2YCW
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yo3ggx
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Re: miniVNA Android controller v0.9.4-6

Post by yo3ggx »

Hi Claudio,

First my apologies for the late answer. For a strange reason this time I was not notified about a new message in the forum.
Usually first recommendation will be to upgrade the firmware.
Next, I suspect that you had somehow done a wrong frequency calibration. Please try to reset the config file using a long press on START button then redo the full calibration.
I see no other reason to have a different frequency reading on BleVNA than on other apps.

Please check and post here your results.

Thank you,
73 Dan YO3GGX
ik2ycw
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Joined: Wed Feb 04, 2015 12:22 pm

Re: miniVNA Android controller v0.9.4-6

Post by ik2ycw »

Dear Dan,

thank you very much for your answer, I do appreciate it.
I have tried to follow your suggestion, i did several reset of the system as you describe, but the result is always the same.
I get a perfect Smith chart, but it's off by 300Khz approximately on 40 meters.

My antenna is resonant at 7,080, but I do read resonance on the VNA connected to Android at 7,351.
If I am looking at the Smith chart it looks exactly as I get it on my SDK or even if I am using the VNA with his original sotware,
but in that case the resonance is correct at 7,080.
I get same result with the original software as well as with the new German software, only with the Android software is off by almost 300Khz.

I wondering if the problem is related to my old version, as you know I can not upgrade my version since my unit is too old (serial 0025).


Thanks

Claudio
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yo3ggx
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Re: miniVNA Android controller v0.9.4-6

Post by yo3ggx »

Hi Claudio,

It seems that units with serial number less than 35 use a DDS clock of 500Mhz instead of 520Mhz as usual.
vnaJ let you adjust the right value, this is the reason that the frequency is ok.
I've prepared a new version fo BlueVNA which allows you to change the DDS clock frequency. You can download it from here:
http://www.yo3ggx.ro/btvna/btvna_v0.9.4-7.apk

If everyithing is ok I will push it to Play Store.

To change it, slide the finger vertically in the startup page over the device info text. You will be prompted to enter the new DDS frequency in MHz . Enter 500 and press SET. The new value will be displayed in the startup page at each application start.
The only accepted values for miniVNA Pro are 500MHz or 520MHz.

Please test it and send me your feedback.

Thank you for reporting this

73 Dan YO3GGX
ik2ycw
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Re: miniVNA Android controller v0.9.4-6

Post by ik2ycw »

Dear Dan,

I do believe that you are correct, the difference is exactly that much.

Unfortunately I am quite inexpert with Android therefore I am not sure how to load the application unless I do it with Play Store.
I tried to connect with my Samsung phone but I get non results.

I did download the file to my PC, but now how to uploaded to the phone?

Thanks
Claudio
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yo3ggx
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Re: miniVNA Android controller v0.9.4-6

Post by yo3ggx »

Hi Claudio,

You can do the following:
- download the application using the PC
- rename the extension to ".apk" if it was chnaged to ".man" during the download
- copy the file using Windows Explorer to your Android device, to the root of the SD card or Internal Storage
- use a file explorer on your device (ex. Total Commander) to launch that apk file.

This is all. I will push it to play store as soon as you confirm that is working as I have no way to test it here.

73 Dan YO3GGX
ik2ycw
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Re: miniVNA Android controller v0.9.4-6

Post by ik2ycw »

Hi Dan,

I was able to load the program to my Samsung Galaxy 5.
The progam has the right firmware version v0.9.4-7 and I can change the DDS value to 500 Mhz.

Unfotunately any action I make with the unit in terms of values acquisition or calibration, I am getting always the same error:

Error occured
An error has occured in sub:
java.lang.StringIndexOutOfBoundsException:
lenght=988; regionStart=-1; regionLength=4
Continue?

If I responde YES, I am getting same error over and over.


I hope you have the solution.

Thanks so much for your help

Claudio
ik2ycw
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Re: miniVNA Android controller v0.9.4-6

Post by ik2ycw »

Dear Dan,

in reality the nature of the problem is always the same, but indeed the values can change such lenght, regionStart and regionLenght
Sorry

Claudio
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Re: miniVNA Android controller v0.9.4-6

Post by yo3ggx »

Hi Claudio,

Please try to reset the configuration file using a long press on START button and then do again a full calibration.

73 Dan YO3GGX
ik2ycw
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Joined: Wed Feb 04, 2015 12:22 pm

Re: miniVNA Android controller v0.9.4-6

Post by ik2ycw »

Hi Dan,

I did try your suggestion , I did the complete reset of the unit.

I still have the same problem.
I have tried several times, I did make sure to reset the unit completely, I reintroduce the DDS equal to 500 and so on, but still I get the same Error.

thanks

IK2YCW
Claudio
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